1. Technical Field
The present inventive concept relates to a semiconductor device and a communication system including the same.
2. Description of the Related Art
Semiconductor and communication technologies are integral to the functioning of the modern world. In general, a conventional phase shift keying (PSK) method is a simple and efficient modulation scheme to transmit signals by shifting a phase. According to the number of corresponding phases, a signal constellation consisting of 2N (N=1, 2, 3, 4, . . . ) points is formed, and is referred to as BPSK, QPSK, 8PSK, 16PSK, . . . according to the value of N. However, since such a signal has certain characteristics to pass through an origin during transition, for example, when passing through a power amplifier (PA), when the PA does not operate linearly, the signal is severely distorted, thereby resulting in a reduction in quality. Thus, it hinders the PA from being used to its maximum capabilities.
Some semiconductor and communication technologies are related to a Near Field Communication (NFC) card. An NFC card is sometimes referred to as a smart card, a chip card, an integrated circuit (IC) card or the like, and may be operated in a passive mode or an active mode according to its operation method. In the passive mode, the NFC card performs an operation of receiving a signal transmitted from a reader. In the active mode, the NFC card performs an operation of transmitting the signal received from the reader together with transmission data back to the reader.